1. Field of the Invention
The present invention relates to a key switch to be used in an electronic apparatus such as a tape printer and particularly to a key switch adapted to restrain the motion of a key part in a direction of a shorter side thereof.
2. Description of Related Art
As one of key switches having a switch function using a contact, a key switch having a plurality of contacts which are selectively operated is disclosed for example in Japanese unexamined patent publication No. H7-235242 (1995-235242). In this switch device, an operating part is made of for example ABS resin by integral molding and a control knob is rotatable about a supporting point of the operating part and a contact part of a supporting point receiver of a guide part. When an operation display is pressed, the control knob is rotated about the supporting point and the contact part of the supporting point receiver, thereby pressing the top of one of a pair of tactile switches to turn the selected tactile switch ON. In this state, one of hinges formed for connecting the control knob with the operating part is bent and the other is extended. When released, the control knob is returned to an initial non-pressed position by a restoration force of the hinges, thus turning the tactile switch OFF.
However, for the use of a single switch, such as the switch device disclosed in the above publication '242, for two-way selection, the switch needs be formed to be elongated (in top view) in a selection direction, for example as shown in FIG. 17. In FIG. 17, a switch 100 tends to more largely move in a direction of a shorter side (a minor axis) as indicated by a double-headed arrow 102 as compared with in a direction of a longer side (a major axis), i.e. the selection direction, as indicated by arrows 101. This would lead to low operationality of the switch and disturb correct operation. When a width of a wall 103 extending radially outwardly from a lower periphery of the switch 100 is small in order to reduce the motion of the switch 100 in the minor axis direction, simultaneously, the switch 100 would also be restrained against motion in the major axis direction.